Button sewing machine



June 9, 1936. M, McCANN 7 2,043,929

' BUTTON SEWING MACHINE FiledMa rch 15, 1935 4 Sheets-Sheet 1 June 9,1936. M. MOCANN 2,043,929

BUTTON SEWING MACHINE Filed March 15, 1935 4 Sheets-Sheet 2 June 9,1936. M. MC ANN 2,043,929

BUTTON SEWING MACHINE Filed March 15, 1955 4 Sheets-Sheet 3 June 9, 1936- M. McCANN 7 2,043,929

I BUTTON SEWING MACHINE Filed March 15, 1955 4 Sheets-Sheet 4 Patented June 9, 1936 UNITED STATES 2,043,929 BUTTON SEWING mcnmr:

Michael McCann, Ozone Park, N. Y., assignor to The Singer Manufacturing Company, Elizabeth,

N. 1., a corporation of New Jersey Application March 15. 1935, Serial No. 11,233 '1 Claims. (or 112-110 This invention relates to sewing machines more particularly of the single-thread chain-stitch type adapted for the sewing of buttons to garments. v

Single-thread chain-stitch button-sewing machines, as commonly constructed, comprise a reciprocatory eye-pointed needle, a rotary looper, and a work-clamp having a lower cloth-supporting plate and upper presser-device including but- 1 ton-gripping jaws which are movable laterally toward and away from one another to grip and release the button, and vertically toward and away from the cloth-supporting plate to hold and release the cloth to which the button is to be attached.

Stitch-positioning means are commonly provided for relatively moving the needle and workclamp during the sewing to distribute thestitches,

as desired, in the holes in the button.

Machines for sewing on four-hole buttons with two independent groups of stitches, and without a connecting or cross-over stitch, as demanded by the clothing trade, have commonly been provided with a stop-motion device which acts to stop the machine at the completion of each of the two groups of stitches, so that the sewing thread may be severed at the completion of the first group of stitches as well as at the completion of the last group of stitches.

The severing of the sewing thread is commonly accomplished after the machine comes to rest, by the act of the operator in lifting the buttonclamp which exerts a strain on the thread leading downwardly from the last stitch and around the looper and thence upwardly through the work and through the needle-eye and an appropriate thread-clamp or thread-tension device to the source of supply. The strain exerted on the thread by the operator in lifting the buttonclamp breaks the thread at the under side of the work close to the last stitch, in a manner well known.

It is necessary in certain button-sewing operar tions to provide the lower cloth-supporting plate or the machine with work-positioning means.

For example, in sewing a button to cloth with stitches which pass through a stay-button below the cloth, it is necessary to provide the clothsupporting plate of the work-clamp with stay- 50 button-positioning means which is usually in the form of a circular stay-button-receiving aperture or pocket. Again, in blind-stitching four-hole buttons to garments, the cloth-supporting plate of the work-clamp is commonly provided with a shoulder for properly positioning a fold of material to receive the button-fastening stitches which are caused to pass alternately through the fold and outside the fold; in a manner well known.

Difiiculty has been experienced in the opera- '5 tion of known machines of the types above indicated because of the fact that in lifting the upper or button-clamping member of the workclamp to break the thread at the completion of the sewing of the first group of stitches, the stay- 10 button or fold of cloth, as the case may be, is raised out of its pocket or separated from its positioning means on the lower cloth-supporting plate and is not properly and certainlyre-engaged with the same when the button-clamp is 15 lowered preparatory to the sewing of the second or final group of stitches. In other words, in prior machines of the type in question, the work, after having been initially placed in the workclamp and partially stitched, is necessarily dis- 2o turbed relatively to the work-clamping and po-- sitioning devices before it is finished. This pre- -mature disturbance of the work in the workclamp is troublesome and requires the operator to exercise considerable care and attention to 25 avoid the production of imperfect work,

The present invention has for an object to provide a sewing machine with a work-clamp which may be lifted to break the sewing thread at the completion of the first of two group-stitch- 30 ing operations, without disturbing the work relative to the work-positioning means customarily associated with the cloth-supporting part of the work-clamp.

Anotherobject oi! the invention is to provide 5 a button sewing machine havingca work-clamp including a lower cloth-support'fand upper button-gripping jaws with means permitting the lower cloth-support to move vertically with the button-gripping jaws as the latter are raised by 40 the operator to break the thread at the end of the first group-stitching operation on a fourhole button, and preventing the cloth-plate from moving vertically with the button-gripping jaws in breaking the thread at the end of the second or final group-stitching operation.

with the above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations, and arrangements of parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodi-' ment or the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

Broadly speaking, the invention, in one aspect thereof, comprises the provision of a sewing machine with a work-clamp including separable work-clamping members which in one stop-position of the parts are movable simultaneously away from the machine bed without disturbing their relative work-clamping relations, and in another stop-position of the parts are relatively separable for removal and insertion of work.

In the accompanying drawings, Fig.1 is a side elevation of a button-sewing machine embodying the invention. Fig. 2 is a section on the line 2-2, Fig. 1, Fig. 3 is a horizontal sectional view through the overhanging bracket-arm of the machine, showing the mechanism for vibrating the needlebar. Fig. 4 is a horizontal section through the bracket-arm standard showing the machine bed and the lower work-clamping plate in locked position on the machine bed. Fig. 5 is a section on the line 5-5, Fig. 4. Fig. 6 is a section on the line 6-8, Fig. 1. Fig. 7 is a view similar to Fig. 4, but on a larger scale, showing the lower work-clamping plate in unlocked position on the machinebed. Fig. 8 is a plan view of the work-supporting end of the lower work-clamping plate with the work-positioning means broken away. Fig. 9 is a front end elevation of the machine. I

Figs. 10 and 11 are views showing details of the stop-mechanism of the machine. Fig. 12 is a section on theline I2-I2, Fig. 7. Fig. 13 is a similar view on the line I 3I3, Fig. 4. Fig. 14 is a view of the lower work-clamping plate locking device on the line I 4I4, Fig. 4. Figs. 15 and 16 are transverse sectional views through the work-- clamp at the sewing point at the respective times when the button-clamp is raised to break the sewing thread at the completion of the first group and second group of stitches in sewing on a fourhole button with an under stay-button. Fig. 17 is a section on the line I1-I1, Fig. 16. Figs. 18 and 19 are transverse sectional views through the work-clamp at the sewing point at the respective times when the button-clamp 'is raised to break the thread at the completion of the first group and second group of stitches in blind-stitching a four-hole button to a folded edge of material.

The machine is constructed with a frame including the bed I from which rises the standard 2 of the overhanging bracket-arm 3 terminating in the head 4. The bed I includes the extension I of reduced wid h constituting a work-supporting arm.

The stitch-forming mechanism is constructed substantially in accordance with the disclosure of U. S. Pa'tentNo. 1,606,173, of Nov. 9, 1926, and comprises the endwise reciprocatory and laterally vibratory needle 5 and rotary non-threaded or wing-type looper 6 actuated in any known manner. The needle 5 is carried by the needle-bar 1 which is given its endwise reciprocatory movements by means of the usual link-connection 8 with the vibratory arm 9 fixed to the rock-shaft I 0 actuated by the pitman-connection I I from the eccentric I2 on the main shaft I3.

The needle-bar is guided in its reciprocatory movements by the upper and lower bearing blocks,

I4 and I5. The upper bearing block I4 is fixed to the pivot-shaft I5 which is journaled in the head 4. The lower bearing block I5 is fixed to the pivot-shaft I1 which is carried by the needle-barvibrating lever I8 fulcrumed on the adjustable fulcrumv-block I 9 and carrying a follower 28 entering the cam-groove 2| in the needle-bar-vibrating cam 22 on the slow vertical feed-shaft 23. The feed-shaft 23 makes one complete rotaone another the shanks 33, 34 of the upper but ton-clamp and lower work-supporting and positioning means.

The shank 34 has rigidly fixed thereto a plate 35 the downwardly and forwardly offset portion 36 of which normally rests in sewing position upon the throat-plate and bed-plate 31. This lower plate 35, 38 has pivotally mounted thereon at 38, and constituting a ,part thereof, a work-positioning plate 39 having atone end a circular stay' button-receiving pocket 40 and at its other end a block 4I having spaced work- 2! positioning shoulders 42 and an intervening needle-clearance notch 43. The plate 39 may be turned end-for-end about its pivot 38 to position either the stay-button-receiving pocket 40 or the blind-stitch guide-shoulders 42 in sewing position. This lower work-positioning device is constructed substantially in accordance with the disclosure of U. S. Patent No. 1,998,587, dated Apr. 23, 1935. The plate 35 is formed at its forward end with a square sewing aperture 44, Fig. 35

8, exposing the needle-slot 28 in the throat-plate 25. The shank 33 carries the usual presserdevice including the upper plate or bar 45 on which are mounted the usual reciprocally mov-' able button-gripping levers 45 the construction and function of which are well understood by those skilled in the art. In the present instance, the upperbar 45 of the work-clamp which carries the button-gripping levers 45 is spring connected to the lower or fabric-supporting bar 35, 35 of the work-clamp, so that when the upper bar 45 is lifted by the operator to break the thread at the end of the sewing oi a group of stitches, the spring connection will yieldingly tend to lift the. lower bar 35, 35 with it. To this end a post 41 is anchored to the lower bar 35 and projects upwardly through a hole 48 in the upper bar 45. The post 41 is surrounded above the bar 45' by a compression spring 46 backed by an adjustable 'nut 50 threaded on the Post 41. The bar 45 is lifted in the usual manner by the chain 5I connecting the bar45 to the arm 52 on the rock-shaft 53 which also has fixed thereto an arm 54 connected to a treadleoperated pull-rod 55.

The upper bar 45 is yieldingly depressed to press or clamp the fabric upon the lower plate 36 by means of the plunger 55 bearing at its lower end upon the bar 45 and slidably mounted in bearings 51, 58 in the arm 3. A spring 59 received in an axial bore in the plunger 56 \d backed by an adjustable thumb-screw 60 exerts the desired fabric-clamping pressure upon the upper clamping bar 45. A collarIiI normally loose on the plunger 59 may be tightened to hold the plunger 56 raised above and clear of the bar 45 in assembling or disassembling the parts of the work-clamp.

. needle Litween group-stitching operations. To

this end, there is adjustably mounted in the slot 30 in the head of the slide-bar 28 a roller-stud 62 which enters the longitudinally slotted arm 63 of a bell-crank lever 63, 64 fulcrumed at 65 on the bed I. The bell-crank lever-arm 64 has a follower 66 which enters the cam-groove 61 in the disk 68 on the slow shaft 23. The camgroove 61 has two concentric semi-circular portions joined by the diametrically opposed eccentric portions or throws 69 which shift the workclamp at the close of each group-stitching operation just before the machine comes to rest.

The machine is equipped with a stop-motion device of known construction such, for example, as that disclosed in U. S. Patent No. 1,983,555, of Dec. 11, 1934. Such a stop-motion device comprises a. power-receiving belt-pulley 10 which is loose on the mainshaft l3 and is movable endwise of the latter to carry a driving stud 1| on the side of the pulley 18 into and out of driving engagement with an'arm 12 fast .on the main shaft l3. The position of the pulley 10 lengthwise of the main shaft I3 is controlled by the inclined head 13 of an arm 14 fixed on the stop-motion control rock-shaft 15 biased by a coil-spring 16 to turn the rock-shaft15 to the stop-position shown in Fig. 1, in which position the inclined head 13 working in the grooved hub 11 of the pulley 10 has shifted the latter so that the stud 1| is out of driving engagement with the arm 12 on the main shaft |3. The rockshaft 15 has'fixed to it'a collar 18 formed with a shoulder 19- which is engaged by a springbiased latch fulcrumed at 8| and rigidly associatedwith a trip-arm 82 in position to be enaged by the diametrically opposed tripping points 83 on the slo haft 23. The latch 88 detains the rock-shaft 15 in machine-running position and, when shifted by one of the tripping points 83, releases the rock-shaft 15 which springs to machine-stopping position, Fig. 1. Since therearegtwo tripping points 83 on the slow-shaft 23, machine will perform two Pivotally mounted at 84 on the machine bed,-

is a latch 85 having a'nose 86 which, at the rearward sewing position of the work-clamp, Fig. 4, overlies the corner 81 of the lower clamp-plate extension 36 adjacent the latch-clearance notch 88 therein, and locks the clamp-plate 35, 36 to the bed I so that it will not be lifted with the upper button-clamp-supporting arm 45when the latter is lifted at the completion of a group of stitches. In the forward sewing position of the work-clamp, Fig. '7, thecorner 81 of the lower clamp-plate is clear of the latch nose 86and hence the lower clamp-plate 35, 36 is, free to rise vith'the button-clamp-supporting arm 45; all parts of the work-clamp rising as a unit and without relative with its adjustable abutment screw 96 in engagement with one of the work-damp guide-bars 21.

' the other of the disturbance of any of the button and cloth-positioning and clamping elements. Y

Operation 39 on the lower clamp-plate 36 which is locked in its lower rearward position upon the throat-plate 25- by the latch 86, as shown in Fig. 4. The main button 9| is inserted in the jaws of the buttongripping levers 46 which are lowered with the button 9| into clamping relation with the bodyfabric 93 upon the lower work-positioning plate 39 which constitutes a part of the lower clampplate 36.

The machine is then started and the needle 5 sews the first group s of stitches through the forwardly disposed pairs of holes in the two buttons 9|, 92. The needle-bar vibrating cam 2| is so cut that the needle makes its last three complete reciprocations through the same holes in the main and stay-buttons without making any lateral movement, and thus causes the usual final knot tying stitches to be formed. After the needle has risen from the work at the completion of the last stitch, one of the throws 69 in the cam 61 shifts the work-clamp forwardly to the position shown in Fig. '7, whereupon one of the stop-motiontripping points 83 releases the stopmotion control rock-shaft 15 and stops the machine.

Just before the machine is stopped one of the rounded knobs 94 on the cam-disk 22 rides under and lifts the lever 95'which acts upon the threadtension device 96 toheavily tension the sewing thread in the usual manner for the thread breaking operation.

work-clamp is in the position shown in Fig. '7,'

in which the corner 81'of the lower clamp-plate 36 is clear of the latch 86.

When the operator exerts a pull upon the rod 55 to raise the button-clamp 45, 46 for the usual thread-breaking operation, the lower clampplate 36 and stay-button-positioning plate 39 carried thereby are free to risewith the work, as shown in Fig. 15, without any disarrangement of the relative positions of any of the work-clamping elements. The stay-button 92 is not lifted out of its pocket 48 at thisincomplete stage of the button-sewing operation and the work-clamp may be instantly lowered and the machine restarted without a moments delay and without the necessity ofthe exercise of any particular care on the part'of the operator.

At the completion of the sewing of the second or final -group s of stitches, including the usual knot-tying stitches, the work-clamp is returned to the position shown in Fig. 4, just before the stop-motion control rock-shaft 15 is released.by two tripping points 83. In this position of the work-clamp the corner 81 of the lower clamp-plate 36 has passed under the latch 86 and the lower clamp-plate 36 and staybutton positioning plate 39 are thus locked against rising from the bed I, Fig. 16, when the button-clamp levers 46 are raised by the operator to break the thread and open the work-clamp for removal of the finished work.'

The operations are the same in blind sewing a four-hole button 91, Figs. 18 and 19, .to a foldedge 98 of fabric. To properly position the foldedge 98, it is customary to turn the work-positioning plate 39 end-for-end to bring the fold-edge-.

. of stitches, Fig. 18, the work-clamp is raised to break the thread and, in this operation, there is no disturbance of the fold-edge 98 relative to the fold-edge-positioning shoulders 42 and usual fabric-clamping foot 98; all parts of the workclamp being raised as a unit. After the final group 8 of stitches has been formed, only the button-gripping levers 46 are raised, Fig. 19, to break the thread and release the fabric for removal from the machine.

The usual vibratory thread-catcher 89, having the thread-catching pocket Hill, Fig. 17, is preferably used to pull the broken needle-thread-end Hll out of the work and releasably detain it to one side of the sewing point for the beginning of the ensuing group-stitching operation. This device is mounted on the clamp-lifting rockshaft 53.

Should an operator lift the work-clamp prematurely', when the lower plate 36 is in unlocked position, Fig. '7, and before the work-clamp has been automatically shifted to the locked position shown in Fig. 4, there is danger that the corner 81 may clash with the latch-nose 86. To avoid breakage of the parts under this cohdition, the latch 85 is pivotally mounted and backed by the spring 89 which permits the latch-nose 86 to yield rearwardly horizontally, should it be struck by the prematurely raised corner 81. The latchnose 86 is beveled at 86' so that the corner 81 may, if prematurely raised above the latch nose 86 and subsequently lowered, engage the beveled snap past the latch-nose 86 to the initial position of the parts shown in Fig. 4.

face 86 in its vertically downward movement and The invention is not to be understood as limited to the deails of construction and relative arrangements of parts shown and described, as such details and relative arrangements may obviously be variously modifled-by those skilled in the art within the spirit of the invention.

Having thus set forth the nature of tion, what I claim herein is:-

1. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, opposed work-clamping members, means yieldingly urgthe invening said clamping members into work-clamping position, means for relatively shifting said needle and work-clamping members crosswise of the path of needle-reciprocation, lifting means connected to one ,of said clamping members and effective to raise said members as a unit in one of the relatively laterally shifted positions of said needle and clamping members, and means restraining one of said clamping members against button-gripping jaws to break the sewing thread,

,port against vertical movement yielding means connecting the button-gripping jaws with the cloth-support to lift the latter with said jaws, and a device for locking the cloth-supin alternate group-stitching operations.

3. In a button-sewing machine, the combination with the machine bed and a feed-cam-actuated member, of a work-support pivoted on said member for upward movement away from normal sewing position on the machine bed, a buttonclamp also pivoted on said member, a spring-connection between said work-support and buttonclamp, means for lifting said button-clamp, and

means controlled by movement of said feed-camactuated member for alternately locking and unlocking said work-support in normal sewing position on said machine bad.

4. A button-sewing machine having, in combination, a frame including a bed, stitch-forming mechanism including an endwise reciprocatory and laterally vibratory needle, 9. work-clamp including lower work-supporting and positioning means and upper button-gripping jaws, means for shifting the work-clamp from one sewing position on said bed to another to successively present the two pairs of holes in a four-hole button to said needle for the sewing therein of two independent groups 01' stitches, means for simultaneously lifting the button-gripping jaws and lower work-supporting and positioning means from said bed to break the thread at the completion of the first group of stitches, and means for retaining the lower work-supporting and positioning means in normal sewing position when the button-gripping jaws are lifted at the completicn of the second group of stitches to break the thread. I

5. A button-sewing machine having a frame including a bed, stitch-forming mechanism including a reciprocatory needle, a work-clamp in'-' cluding;,a lower work-supporting plate and an upper button-holder each pivotally carried by said bed and each pivotally movable independently of the other, manually operated means for lifting said button-holder, spring means connect- .ed to said button-holder for lifting} said lower plate from said bed, and hold-down means on said bed for at times retainingsaid lower plate on said bed when said button-holder is lifted.

6. In a work-clamp for sewing machines, a bed, upper and lower work-clamping members on said bed, manually operated means to lift the upper clamping member, spring means connected to the upper clamping member to yieldingly lift the lower clamping member, and unyielding means for at times retaining the lower clamping member in normal position on said bed when the upper clamping member is lifted.

7. A sewing machine having, in combination, stitch-forming mechanism including a reciprocatory needle, 9. work-clamp includinga lower clamp member and an upper clamp member movable towardand away from said lower clamp member, means for relatively moving said needle and work-clamp to sew two differently located groups .of stitches in the work, a stop-motion device arranged to stop the machine at the completion of each of said groups of stitches, and manually operated means to simultaneously lift and simultaneously lower both clamp members at' the close of the first group-stitching operation and to lift and lower the upper clamp member only, at the close of the following group-stitching operation. McCANN. 

